Researchers set to warn Congress of cloning risks

Plans by 2 groups to try to replicate humans prompt House hearing

March 28, 2001|By BOSTON GLOBE

With at least two maverick groups announcing plans to try to genetically replicate human beings, scientists are preparing to testify before Congress this week that such ventures are likely to yield infants who are deformed or illness-prone, or with undetectable health complications.

Even if the idea won moral approval - which most scientists and ethicists agree is unlikely - researchers point to a wide range of defects affecting cloned animals that are not understood and would probably show up in humans.

Cloning is a method of making genetically identical copies of living cells and has been used with varied success in experiments that created genetic twins of living mice, sheep and other animals.

But many of the replicated animals were born with or developed genetic defects. What most disturbs anti-cloning scientists such as Dr. Rudolf Jaenisch at the Whitehead Institute in Cambridge, Mass., is that unlike birth defects caused by mutant genes, the malformations that cloning can wreak can't be detected by prenatal diagnosis.

"These clones - if they're ever produced - might not show that anything's wrong until they begin socializing or going to school," Jaenisch said. Would-be cloners who say they could diagnose problems before birth, he added, "are ignorant of the science."

Jaenisch is scheduled to testify today before the Subcommittee on Oversight and Investigations of the House Energy and Commerce Committee. Announcements of cloning plans prompted the hearing, which is being held to determine whether the Food and Drug Administration has authority to regulate clinical research in human cloning. The FDA asserts that it does.

The United States has no outright ban on human cloning, though some states do, but public funds can't be used for such research. Professional groups are opposed to it.

Since the birth of Dolly the cloned lamb, scientists have cloned mice, cows, goats and pigs. But it takes dozens or sometimes hundreds of attempts to succeed.

Many of the offspring are larger than normal or have malformed organs. Many become obese, and the longevity of the animals isn't yet known.